Validation of self-reported weights and heights in the avoiding diabetes after pregnancy trial (ADAPT)

Background: Randomized controlled trials that test the effectiveness of mobile health-based weight loss programs are attractive to participants, funders, and researchers because of the low implementation cost, minimal participant burden, and the ability to recruit participants from longer distances. Collecting weight data from geographically dispersed participants is a challenge. Relying on participant self-report is one approach to data collection, but epidemiologic studies indicate that self-reported anthropometric data may be inaccurate. Methods: We provided women enrolled in a randomized controlled trial (RCT) of postpartum weight loss after gestational diabetes with a digital scale and training to collect and report weight via a web-based survey. To validate self-reported weights and heights, we visited 30 randomly selected women in their homes, with a reference scale and stadiometer, a mean of 34 days after the self-report. We ran linear regression models to identify characteristics that were associated with underreporting or overreporting of anthropometric measures. Results: Of the 30 women we visited, 11 women (37%) were assigned to the weight loss intervention group and 19 women (63%) were in the control group. Mean age was 38.5 years (SD 4.5). The overall mean difference between participants’ self-reported weights and the weights obtained at their home visit was 0.70 kg (+1.92). Women assigned to the intervention group underreported their weight in comparison with the control group by 1.29 kg (95% CI −2.52, −0.06). The overall difference in collected to self-reported height was −0.56 cm (±1.91). No characteristics were associated with underreporting or overreporting of height. Conclusions: Our research suggests that by providing a digital scale and developing a weight collection protocol, researchers can train women to collect and record their own study weights with reasonable validity. To achieve the level of validity required for clinical trials, researchers should consider additional strategies to assure the validity of the data. Trial registration NCT01923350

Sex-Specific Associations of Gestational Glucose Tolerance With Childhood Body Composition

OBJECTIVE To examine the associations of maternal gestational glucose tolerance with offspring body composition in late childhood. RESEARCH DESIGN AND METHODS Among 958 women in the prebirth cohort Project Viva, glucose tolerance was assessed in the second trimester by nonfasting 50-g 1-h glucose challenge test (GCT), followed if abnormal by fasting 100-g 3-h oral glucose tolerance test (OGTT). We categorized women as normoglycemic (83.3%) if GCT was ≤140 mg/dL, isolated hyperglycemia (9.1%) if GCT was abnormal but OGTT normal, intermediate glucose intolerance (IGI) (3.3%) if there was one abnormal value on OGTT, or gestational diabetes mellitus (GDM) (4.5%) if there were two or more abnormal OGTT values. Using multivariable linear regression, we examined adjusted associations of glucose tolerance with offspring overall (N = 958) and central (N = 760) adiposity and body composition using dual X-ray absorptiometry (DXA) measured at the school-age visit (95 ± 10 months). RESULTS Compared with that in the male offspring of normoglycemic mothers, DXA fat mass was higher in male offspring of GDM mothers (1.89 kg [95% CI 0.33–3.45]) but not in male offspring of mothers with IGI (0.06 kg [−1.45 to 1.57]). DXA trunk-to-peripheral fat mass, a measure of central adiposity, was also somewhat higher in male offspring of GDM mothers (0.04 [−0.01 to 0.09]). In girls, DXA fat mass was higher in offspring of mothers with IGI (2.23 kg [0.12–4.34]) but not GDM (−1.25 kg [−3.13 to 0.63]). We showed no association of gestational glucose tolerance with DXA lean mass. CONCLUSIONS In this study, only male offspring of GDM mothers manifested increased adiposity, whereas only female offspring of mothers with IGI did so. Sex differences in glycemic sensitivity may explain these findings

Gestational weight gain and child adiposity at age 3 years

OBJECTIVE The purpose of this study was to examine the associations of gestational weight gain with child adiposity. STUDY DESIGN Using multivariable regression, we studied associations of total gestational weight gain and weight gain according to 1990 Institute of Medicine guidelines with child outcomes among 1044 mother-child pairs in Project Viva. RESULTS Greater weight gain was associated with higher child body mass index z-score (0.13 units per 5 kg [95% CI, 0.08, 0.19]), sum of subscapular and triceps skinfold thicknesses (0.26 mm [95% CI, 0.02, 0.51]), and systolic blood pressure (0.60 mm Hg [95% CI, 0.06, 1.13]). Compared with inadequate weight gain (0.17 units [95% CI, 0.01, 0.33]), women with adequate or excessive weight gain had children with higher body mass index z-scores (0.47 [95% CI, 0.37, 0.57] and 0.52 [95% CI, 0.44, 0.61], respectively) and risk of overweight (odds ratios, 3.77 [95% CI: 1.38, 10.27] and 4.35 [95% CI: 1.69, 11.24]). CONCLUSION New recommendations for gestational weight gain may be required in this era of epidemic obesity

Maternal Depressive Symptoms Not Associated with Reduced Height in Young Children in a US Prospective Cohort Study

Background: Shorter stature is associated with greater all cause and heart disease mortality, but taller stature with increased risk of cancer mortality. Though childhood environment is important in determining height, limited data address how maternal depression affects linear growth in children. We examined the relationships between antenatal and postpartum depressive symptoms and child height and linear growth from birth to age 3 years in a U.S. sample. Methods: Subjects were 872 mother-child pairs in Project Viva, a prospective pre-birth cohort study. The study population is relatively advantaged with high levels of income and education and low risk of food insecurity. We assessed maternal depression at mid-pregnancy (mean 28 weeks' gestation) and 6 months postpartum with the Edinburgh Postnatal Depression Scale (score > = 13 on 0–30 scale indicating probable depression). Child outcomes at age 3 were height-for-age z-score (HAZ) and leg length. HAZ was also available at birth and ages 6 months, 1, 2, and 3 years. Findings: Seventy (8.0%) women experienced antenatal depression and 64 (7.3%) experienced postpartum depression. The mean (SD) height for children age 3 was 97.2 cm (4.2), with leg length of 41.6 cm (2.6). In multivariable linear regression models, exposure to postpartum depression was associated with greater HAZ (0.37 [95% confidence interval: 0.16, 0.58]) and longer leg length (0.88 cm [0.35, 1.41]). The relationship between postpartum depression and greater HAZ was evident starting at 6 months and continued to age 3. We found minimal relationships between antenatal depression and child height outcomes. Conclusion: Our findings do not support the hypothesis that maternal depression is associated with reduced height in children in this relatively advantaged sample in a high-income country

Environment and Obesity in the National Children\u27s Study

Objective: In this review we describe the approach taken by the National Children’s Study (NCS), a 21-year prospective study of 100,000 American children, to understanding the role of environmental factors in the development of obesity. Data sources and extraction: We review the literature with regard to the two core hypotheses in the NCS that relate to environmental origins of obesity and describe strategies that will be used to test each hypothesis. Data synthesis: Although it is clear that obesity in an individual results from an imbalance between energy intake and expenditure, control of the obesity epidemic will require understanding of factors in the modern built environment and chemical exposures that may have the capacity to disrupt the link between energy intake and expenditure. The NCS is the largest prospective birth cohort study ever undertaken in the United States that is explicitly designed to seek information on the environmental causes of pediatric disease. Conclusions: Through its embrace of the life-course approach to epidemiology, the NCS will be able to study the origins of obesity from preconception through late adolescence, including factors ranging from genetic inheritance to individual behaviors to the social, built, and natural environment and chemical exposures. It will have sufficient statistical power to examine interactions among these multiple influences, including gene–environment and gene–obesity interactions. A major secondary benefit will derive from the banking of specimens for future analysis

Achieving Cardiovascular Health in Young Adulthood—Which Adolescent Factors Matter?

AbstractPurposeTo examine associations of adolescent body mass index (BMI), tobacco use, and physical activity with optimal physiologic cardiovascular health (CVH) in adulthood.MethodsData were from 12,139 participants in Waves I (1995–1996) and IV (2007–2008) of the National Longitudinal Study of Adolescent Health. We defined optimal CVH as normal blood pressure, glucose, and cholesterol without diabetes or cardiovascular disease. We used logistic regression to estimate odds of having optimal CVH at ages 24–32 years (Wave IV) according to BMI category, smoking status, and physical activity at ages 11–19 years (Wave I).ResultsFew young adults (16%) had optimal CVH. Adolescents with normal BMI were more than twice as likely to have optimal young adult CVH compared to those who were obese (adjusted odds ratio, 2.77; 95% confidence interval, 1.97–3.89). Adolescent smoking and physical activity did not predict young adult CVH.ConclusionsLower adolescent BMI is associated with young adult CVH

Maternal age and other predictors of newborn blood pressure

Objective To investigate perinatal predictors of newborn blood pressure. Study design Among 1059 mothers and their newborn infants participating in Project Viva, a US cohort study of pregnant women and their offspring, we obtained five systolic blood pressure readings on a single occasion in the first few days of life. Using multivariate linear regression models, we examined the extent to which maternal age and other pre- and perinatal factors predicted newborn blood pressure level. Results Mean (SD) maternal age was 32.0 (5.2) years, and mean (SD) newborn systolic blood pressure was 72.6 (9.0) mm Hg. A multivariate model showed that for each 5-year increase in maternal age, newborn systolic blood pressure was 0.8 mm Hg higher (95% CI, 0.2, 1.4). In addition to maternal age, independent predictors of newborn blood pressure included maternal third trimester blood pressure (0.9 mm Hg [95% CI, 0.2, 1.6] for each increment in maternal blood pressure); infant age at which we measured blood pressure (2.4 mm Hg [95% CI 1.7, 3.0] for each additional day of life); and birth weight (2.9 mm Hg [95% CI, 1.6, 4.2] per kg). Conclusions Higher maternal age, maternal blood pressure, and birth weight were associated with higher newborn systolic blood pressure. Whereas blood pressure later in childhood predicts adult hypertension and its consequences, newborn blood pressure may represent different phenomena, such as pre- and perinatal influences on cardiac structure and function. Development of risk for adult cardiovascular disease begins very early in life, even before birth.1 Data are scarce, however, regarding blood pressure in the newborn period, which may reflect pre- and perinatal influences on cardiac structure and function. The few studies that have examined determinants of newborn blood pressure suggest a direct association with birth weight,2.; 3.; 4.; 5.; 6.; 7.; 8.; 9. ; 10. in contrast to the inverse association seen with older infants, children, and adults.11 However, most of these studies have at least one important limitation, such as a relatively small sample size of term newborns, lack of data on potentially confounding variables, and limited data on maternal predictors. Maternal age is of particular interest given the known associations of advanced age with adverse reproductive outcomes, including reduced fertility, preterm birth, impaired fetal growth, multiple birth, and congenital anomalies.12.; 13. ; 14. The additional associations of advanced maternal age with diabetes and hypertension,15. ; 16. with possible diminished uterine vascular and placental function,17. ; 18. and in at least two reports with blood pressure level in childhood and in adolescence19. ; 20. warrant examination of its influence on newborn blood pressure. The purpose of this analysis was to investigate associations of pre- and perinatal factors, including maternal age, with systolic blood pressure level during the first few days of life among members of Project Viva, a cohort study of pregnant women and their children

Correlations among adiposity measures in school-aged children

BACKGROUND: Given that it is not feasible to use dual x-ray absorptiometry (DXA) or other reference methods to measure adiposity in all pediatric clinical and research settings, it is important to identify reasonable alternatives. Therefore, we sought to determine the extent to which other adiposity measures were correlated with DXA fat mass in school-aged children. METHODS: In 1110 children aged 6.5-10.9 years in the pre-birth cohort Project Viva, we calculated Spearman correlation coefficients between DXA (n=875) and other adiposity measures including body mass index (BMI), skinfold thickness, circumferences, and bioimpedance. We also computed correlations between lean body mass measures. RESULTS: 50.0% of the children were female and 36.5% were non-white. Mean (SD) BMI was 17.2 (3.1) and total fat mass by DXA was 7.5 (3.9) kg. DXA total fat mass was highly correlated with BMI (r(s)=0.83), bioimpedance total fat (r(s)=0.87), and sum of skinfolds (r(s)=0.90), and DXA trunk fat was highly correlated with waist circumference (r(s)=0.79). Correlations of BMI with other adiposity indices were high, e.g., with waist circumference (r(s)=0.86) and sum of subscapular plus triceps skinfolds (r(s)=0.79). DXA fat-free mass and bioimpedance fat-free mass were highly correlated (r(s)=0.94). CONCLUSIONS: In school-aged children, BMI, sum of skinfolds, and other adiposity measures were strongly correlated with DXA fat mass. Although these measurement methods have limitations, BMI and skinfolds are adequate surrogate measures of relative adiposity in children when DXA is not practical